Multiple targets are attacked and an explosion occurs in Tehran, Iran on February 28, 2026. Photo: IC

According to Mehr News Agency on Sunday, the Iranian government issued a statement following the martyrdom of Iran's Supreme Leader, Ayatollah Ali Khamenei, vowing to make the enemies "pay a heavy price" with "all its strength and determination." The statement declared a 40-day period of national mourning and a 7-day shutdown of public institutions, Xinhua News Agency reported.

The US and Iran launched large air strikes on Tehran and other Iranian cities on Saturday local time, prompting retaliatory operations from Iran.

The latest Iranian government statement came after the news of its Supreme Leader Ayatollah Ali Khamenei's death. The statement also said that the Iranian people would unite as one to overcome the difficulties, per Xinhua.

Iranian President Masoud Pezeshkian has denounced Khamenei's killing "as a great crime" and promised to respond, according to a statement from his office, Al Jazeera reported.

The official IRNA news agency reported that a three-person council, consisting of the country's president, the chief of the judiciary, and one of the jurists of the Guardian Council, will temporarily assume all leadership duties in the country.

According to Iranian state media, the Islamic Revolutionary Guard Corps (IRGC) said it is carrying out a sixth wave of attacks in retaliation for the US and Israeli bombardment of Iran, according to Iranian state media.

It said it has launched "extensive missile and drone" attacks on Israel and US military bases in the region. It said 27 US bases, as well as the Israeli Tel Nof airbase, the Israeli army's command headquarters at HaKirya in Tel Aviv, and a large defense industrial complex in the same city, were attacked.

There has been no official confirmation of the information by the US or Israel.

CNN News reported that Iran launched a fresh wave of strikes across the Middle East Sunday morning, with explosions heard by CNN teams in several capitals and major cities.

The Israeli military has warned residents to refrain from sharing the locations of areas hit by Iranian bombardment, as retaliatory strikes continue.

US President Donald Trump warned Iran against continued retaliation, saying in a social media post that they would be met with excessive force from the US.

"Iran just stated that they are going to hit very hard today, harder than they have ever been hit before," the Trump wrote in a post on Truth Social on Sunday. "THEY BETTER NOT DO THAT, HOWEVER, BECAUSE IF THEY DO, WE WILL HIT THEM WITH A FORCE THAT HAS NEVER BEEN SEEN BEFORE!" he added.

On Sunday, Ali Larijani, Secretary of the Supreme National Security Council said that: "The Americans have stabbed the Iranian people in the heart and we will stab them in their heart," CNN reported.

He promised further retaliation against the US and Israel, saying the "reaction from our armed forces will be much stronger."